Flashcards in RWD - Medicinal chemistry Deck (13):
What is a prodrug?
A biologically inactive compound which can be metabolized in the body to produce a drug.
Drug latentiation is...
... the chemical modification of a biologically active compound to form a new compound, which in vivo will liberate the parent compound either via enzymatic or non enzymatic reactions (chemical hydrolysis, dissociation etc.)
Why do we need pro-drugs?
1. Not absorbed from GI tract due to polarity, or not through skin or BBB
2. The drug may be unstable
3. Drug may cause toxicity
4. So it can be metabolised at site of action
5. Lack of site specificity
6. Formulation problems
7. Water insoluble
Name three water soluble B vitamins.
Vit B 1 - thiamine
Vit B 2 - riboflavine
Vit B 6 - pyridoxine
Although water soluble B vitamins are actively absorbed, what is the problem with this?
Active absorption can easily be inhibited or saturated.
No quaternary N results in?
good absorption into GI tract
What are some factors that affect dermal absorption?
Basically factors that affect skin hydration:
- presence of urea
- vehicle formation
Benefits of sustained/ prolonged release of drugs
- reduces risk of toxicity
- avoids peak and valley effects seen with fast release drugs
- improves patient compliance
- avoids night time dosing
- can reduce total amount of drug needed
- reduces incidence of GI side effects
- reduces frequency of doses needed to be given
Activity depends not only on the ____ of the drug but also the _____ of the pro-drug into active form
Carbamate ester prevents _____ s that most of the dose reaches the liver intact.
Precipitation at injection site leads to _______ absorption
Advantages of parenteral administration?
- quick blood levels obtained
- allows delivery when oral therapy not feasible
- efficient delivery, especially for drug testing